The invention relates to the automated manufacturing of a three-dimensional object whose design has been created with a computer aided design (CAD) machine.
Modern day manufacturing technology continues to grow in complexity and sophistication. The result is a great need for flexibility in the manufacturing process. Several systems and methods for manufacturing three-dimensional objects which have been designed on a computer have been proposed. However, turning a computer aided design into a solid three-dimensional object quickly and inexpensively remains a problem to which considerable attention need be given.
Technology, commonly referred to as direct cad manufacturing (DCM), has been rapidly developing. In desk top manufacturing, a three-dimensional object is created on a computer screen using a CAD program. Any physical product that is designed, shaped, or prototyped prior to production could benefit from DCM. Industries that may use DCM include automotive, aerospace, appliance, toy manufacturers, and any process that involves the design, redesign, prototyping, and production of three-dimensional models, molds, patterns, or short production runs. Designs that once required weeks or months to be turned into actual models or prototypes can become objects in a matter of hours or days using DCM. Using DCM, a design can be recalled from a library and the object manufactured in just a short period of time, thus eliminating the need for large inventories. Basically, there are five identifiable desk top manufacturing systems and methods.
First is ballistics particle manufacturing as disclosed in U.S. Pat. No. 4,665,492. In this system, the coordinates of a three-dimensional design are stored in a computer data base. Particles are directed to specific locations and built up and deposited to construct the desired object. Second, in photochemical machining, shapes are formed by the polymerization of a monomer, or by sculpting a solid block of plastic, for example, see U.S. Pat. Nos. 4,078,229; 4,238,840; and 4,571,377. In polymerization, one laser may pump a photo initiator or photosynthesizer, while a second laser pumps energy. Polymerization takes place where the two beams intersect. When using the other sculpting technique, a block of rigid plastic is carved by degrading material at the intersection of the two beams. Third is laminated object manufacturing where objects are constructed by the successive definition of thin layers of powdered plastics or metals, thin layers of powder are deposited, then compressed with a heated press platform or by roller compression. Pulses from a single laser then sinter or melt the powder in the desired cross-sectional shape and to the required depth. An example of this type system can be seen in U.S. Pat. No. 4,752,352. Fourth is selective laser sintering where objects may be fabricated by the successive deposition and sintering of thin layers of powdered material, either plastic or metal. The powder layers are spread by a feeding mechanism, but are not compressed. Sintering energy can come from a laser or other suitable direct beam of energy. Fifth, stereolithography is a form of stereolithographic printing wherein a single laser beam cures successive thin layers of liquid monomer by a series of controlled photopolymerization reactions such as shown in U.S. Pat. No. 4,575,330.
Further, U.S. Pat. No. 4,749,347 discloses a topology fabrication apparatus in which a three-dimension solid body having a predetermined topography is automatically manufactured using an extrusion process. Thin sections of the solid body are extruded and successively built up next to each other to form the topographical form such as a topology model made from topographical map information. This system requires a fairly sophisticated apparatus and control for forming what is a relatively simple form. The types of objects which can be made with such an apparatus and control are relatively limited.
Accordingly, it can be seen that the field of desk top manufacturing or computer aided manufacturing is one in which considerable activity and attention need to be given. While the above systems and methods are all candidates for a practical system, a need for the development of more reliable and practical systems and methods still exists.
Accordingly, an important object of the present invention is to provide a method and system for the computer aided manufacture of three-dimensional objects which is reliable and practical.
Another object of the present invention is to provide a system and method for automatically manufacturing three-dimensional objects whose design has been created on a CAD machine using practical hardware and methods.
Another object of the present invention is to provide a system and method for automatically manufacturing a three-dimensional object whose design has been created on a CAD machine wherein the object may be accurately formed in a simple and reliable manner under ordinary manufacturing.